The present invention relates to a polymeric foam, particularly a styrenic foam.
Thermoplastic foams such as styrenic polymer foams, are widely used in the fields of construction, civil engineering and thermal insulation. The styrenic polymer foam suitable for such applications desirably is extruded and has good dimensional stability and relatively small cells. These foams are the so-called extruded foams. Extruded foams are also employed in the so-called decorative field wherein a foam plank may be cut into a decorative foam and be used as is or used as a base for further decorative material. For a considerable period of time, styrenic polymer foams have been extruded employing a variety of organic blowing agents, such as chlorofluorocarbons (CFC's), hydrochlorofluorocarbons (HCFC's) and other halogenated hydrocarbons as well as mixtures thereof. However, large efforts currently are being made to replace CFC's, and other fully halogenated hydrocarbons with environmentally more acceptable blowing agents due to increased environmental concerns about ozone depletion, greenhouse effects and air quality in general.
It would be highly desirable to provide a process for preparing a low density styrenic polymer foam using a partially or entirely pristine, i.e. nonhalogenated, blowing agent. Furthermore, it also would be highly desirable to provide a low density styrenic polymer foam, prepared using a partially or entirely pristine blowing agent, with improved processability without sacrificing other physical properties such as compressive strength and dimensional stability.